JPS5918151A - Cement admixing aggregate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an aggregate used by being mixed with cement.

Concrete structures are generally constructed on the surface by applying a coating material such as mortar to the surface of the concrete base once it has hardened. This surface application is performed through the steps of undercoating, intermediate coating, and finishing coating, and conventionally, the coating material used for this is cement mortar, which is made by mixing cement with sand as an aggregate and mixing it with water. It's here. However, if this is applied directly to a dry concrete base, the moisture in the mortar will permeate into the concrete base, causing the mortar to peel off. Therefore, when applying the undercoat, it is necessary to apply a synthetic resin liquid to the concrete base surface in advance, or to apply a thin layer of cement mixed with water to prevent water permeation. In addition, the smooth surface of this undercoat makes it difficult to overlay cement mortar on top of it, so it is necessary to make the undercoat surface rough by making it rough, which is a disadvantage in that it takes a lot of time to apply the surface.

As a coating material for surface application, it is desirable to have a coating material that is easy to apply and that does not easily cause cracks or peeling after application.In order to meet these demands, we have developed styrofoam with crush grooves on the surface. An architectural undercoat admixture has been proposed that mainly consists of granules and is a mixture of a binder such as glass fiber and a water-retaining and caking powder (
Special Publication No. 52-29331).

If this admixture is used as an aggregate in place of conventional sand and mixed with cement and kneaded with water to make a mortar coating material, the moisture contained in the porous structure of the Styrofoam particles will quickly drain the moisture from the mortar into the concrete. It is said that the phenomenon of absorption into the substrate is alleviated, so it is possible to apply an undercoat without having to slag. In addition, since the styrofoam granules make the undercoat surface rough, it is said that it is possible to apply an intermediate coat without creating combs.

However, in the above-mentioned undercoat admixture, since the specific gravity of expanded polystyrene is light, the fine particles themselves are easily scattered. In addition, if the foamed polystyrene granules alone have a weak bond with the cement, there is a risk of cracking or peeling of the applied material after construction, so a binder such as glass fiber and caking powder are mixed with this. It is constituted as a mixture of powder and granules. In such a mixture of different types of powder and granules, especially in a dry state, static electricity is likely to be generated due to mutual friction, and it is a well-known phenomenon that fine particles repel each other. Manufacturing process.

For example, when a product is stored in a container such as a bag or used when the container is opened, a large amount of dust is generated, which may impair the working environment, harm the health of a worker, or cause a dust explosion. Difficult to handle.

In addition, the expanded polystyrene granules themselves have water retention properties but do not have water permeation prevention properties, so if the concrete base is too dry, the moisture in the mortar will be absorbed into the concrete base rapidly and without interruption, resulting in overdrying of the mortar. Adhesive strength to the substrate decreases. Therefore, it is necessary to spray sufficient water on the concrete base before undercoating, which is time-consuming.

Furthermore, since a material such as glass fiber is mixed as a binder, the application cannot be done by spraying.
There were problems such as trowel application, which worsened workability when the application area was large.

This invention was made in view of these conventional problems, and consists of cement in which the porous surfaces of synthetic resin foam particles are coated with an emulsion-type binder that has high caking properties, high water resistance, and is compatible with cement and sand. The aim is to solve the above problems by providing an aggregate for mixing.

As the synthetic resin foam of the present invention, in addition to foamed styrene, for example, polyurethane foam, polystyrene foam, polyvinyl chloride foam, foamed polyethylene, etc. can be used. The particle size of the synthetic resin foam particles obtained by crushing these foams is adjusted as appropriate depending on the application, but for example, in the case of aggregate for mortar for intermediate coating, 21111
In the case of undercoating, Fi 5 to 6 fins are suitable.

According to this invention, the porous surface of the synthetic resin foam particles is coated with a binder to improve the specific gravity of one particle, caking property, water resistance, etc.
Mixability with cement 1 Modification to improve dispersibility and adhesion. As a binder used for this purpose, an asphalt emulsion is suitable. This is an emulsion in which asphalt is made into fine particles (1 to 3 μm) using an emulsifier and uniformly dispersed in water. Easy to electrically adhere to porous surfaces. Further, even after adhesion, it is not susceptible to the effects of heavy rain and humidity and is easy to decompose and harden relatively quickly, making it suitable.

The surface of the synthetic resin foam particles is coated with this emulsion by a conventional method such as spraying, scattering, or dipping at room temperature.
Asphalt fine particles with a concentration of 2 to 7% are uniformly adhered to the porous surface.

In addition, as a binder, in addition to asphalt emulsion, for example, E
It is also possible to use emulsions of synthetic resins such as VA (ethylene vinyl acetate copolymer).

The aggregate for cement mixing obtained in this way is not a solid substance that is difficult to scatter due to the increased particle weight, but the surface of each particle is highly adhesive, and even fine particles are resistant to relatively large particles. Therefore, unlike conventional admixtures such as non-surface-treated expanded polystyrene particles, there is no risk of generating dust during handling.

Next, an embodiment of the present invention will be described with reference to the drawings. Particles 1, which are made by crushing expanded polystyrene resin and coating the surface with an asphalt cationic emulsion as an aggregate of the present invention, are mixed with cement to form, for example, the surface of a concrete base 2. For construction, use conventional admixtures and #1 as well as cement 4.
Per 0 Ky, approximately 50 cubic σ of the aggregate for undercoat of the present invention and 20 A' of water are added and thoroughly mixed to obtain undercoat application material 3. Incidentally, if necessary, a suitable amount of sand mixed therein or a water retaining agent such as calcium chloride may be added. This coating material is applied to the concrete base surface several times thick by troweling or spraying. Then, a part of the asphalt emulsion adhering to the aggregate surface is absorbed into the concrete base 2 together with the water in the coating material 3, forming a water-proof film on the base surface, so that the water in the coating material 3 becomes excessive. Absorption into the concrete base 2 can be prevented. In addition, the asphalt emulsion particles electrically adhere strongly to the surfaces of cement particles and sand particles due to their positive charges, and gradually harden as the hydration reaction of cement progresses.
J-T adheres extremely strongly to the base 2 and hardens. Therefore, it is possible to completely prevent the phenomenon of peeling of the synthetic resin foam particles 1 themselves as aggregates or the coating material 3, or the phenomenon of cracks occurring on the surface of the solidified coating material 3, without a bond such as a glass fiber.

To apply an intermediate coating to the solidified undercoat surface 3a, use an intermediate coating material 4 prepared by mixing the intermediate coating aggregate 1 of the present invention with cement and water in the same manner as described above.

Apply with a trowel or spray as above. At this time, since the undercoat surface 3a is roughened by the aggregate particles l of the synthetic resin foam, there is no need to go to the trouble of making combs on that surface, and the moisture in the intermediate coat material 4 can still be absorbed by the action of the asphalt emulsion. There is no rapid loss of the adhesive, and the adhesion is extremely strong.

After the intermediate coating material 4 has solidified, the surface 4a may be coated with cement slag 5 and finished.

As explained above, according to the present invention, the porous surface of synthetic resin foam particles is coated with an emulsion type binder to form an aggregate for mixing in cement.
It does not generate dust when it is packaged, opened, or mixed with cement, making it extremely easy to handle, and it is also very easy to work with, as it can be applied not only with a trowel, but also by spraying.

In addition, because it is coated with an emulsion that blends well with cement and gradually hardens to form a strong water-proof film, the cement mixed with this aggregate hardens quickly and increases adhesiveness, making it strong and durable. Surface construction is possible. Also, the porous structure of the synthetic resin foam particles improves the insulation and heat retention of the wall surface.

Furthermore, since it is not bulky, various effects such as being able to make the packaging more compact can be obtained.

[Brief explanation of the drawing]

The figure is a sectional view of an embodiment in which the aggregate according to the present invention is mixed with cement and used for surface construction of a concrete base. 1... Aggregate 2... Concrete base 3... Undercoat 4... Intermediate coat 5...・・・・・・Top coat 269-7 ja

Claims (1)

[Claims] 0) An aggregate for mixing with cement, characterized in that the porous surfaces of synthetic resin foam particles are coated with an emulsion type binder. (2) The aggregate for mixing with cement according to claim 1, wherein the binder is an asphalt emulsion.